Fixes issue #172

The client connection factory created by RxContexts was not having the reference to the eventsubject.
This made the connection factory create a fresh subject.
Fixed the same and added the testcase for this.
Updates CHANGES.md for 0.3.7
Merge branch 'master' of https://github.com/Netflix/RxNetty
Fixed build failure
Merge pull request #173 from NiteshKant/master

Fixes issue #172